Early transmission service worth it?

Speaking of drain and fill procedure, does anyone have the official word from Toyota on how this is done? I thought I had seen copies of service manual pages but can only find a TSB for the 2007 MY.

There seems to be a lack of consensus among members here of almost every aspect of doing this. One person said his newer Gen 2.5 didn't have the pin 13 in his OBDI port. I plan to use the jumper trick to put mine in trans fluid check mode to get the idle down so I'm hoping the 21 MY accepts that process. One more question...Since I run a scangauge and I'm pretty sure the scangauge plug has both male and female ends, can I leave the scangauge plugged in while the jumper between 4 and 13 is used? Sure hate to smoke something.

Edit: Right after posting this I pulled the OBDI connector down where I could see it. First off the scan gauge connector is closed on one side so it must come off for the jumper trick. Second, my 21 does not have a pin 13 so the paperclip trick is out.
At 73* this morning it took my truck 8 minutes to reach 115* fluid temp. The idle had settled long before that so I have little concern about lowering the idle speed when checking.



Another Edit: Job done. As mentioned in a quote to 2muchfun I found my trans overfilled by 10oz. I drained the fluid and got 3 qts on the nose after removing the excess 10oz. I put 3 qts plus 8oz back in and did the check procedure again. This time only 8oz came out so I should be spot on. BTW, with a full tank of gas the trans pan was level.

The worst part about the whole job was there were four concrete slabs with the expansion joints coming together in the exact spot where my creeper wheels decided they needed to be.

 

I found it in 2015+Toyota+Tundra+Repair+Manual_N16 AB60F transmission

On p20-28, p352, p438, p439

 

Why not just use the temp reading from the scan guage? You should get really close just measuring what you drain and putting the same amount back in as long as it's about the same temperature.

 

Two reasons: the TSB for the 2007 mentioned inaccurate readings if the idle wasn't reduced while in check mode and how do I know the amount in there now is correct?
I'm going to put the truck on ramps and level it, put a big ass fan blowing under it and once cooled repeat what I did this morning and once 115* is reached, pull the overflow plug to see what comes out. If any.
I have a translucent 5 gal bucket I'm going to mark graduations so I'll know close to exactly how much came out.
I'll drain overnight and fill in the morning.

Edit: I checked it starting at 116 and finished at 126* F and got out 10oz of fluid before it trickled. So it was 10oz overfilled.

 

Yeah, I saw that doing the jumper reduced the idle and I also considered that someone else maybe didn't fill it or check it properly the first time. Both are logical reasoning and you seem to have a logical plan too. Just be sure to loosen up the fill plug before you drain a drop. If you ever added a cooler, don't forget to pin open the thermostat as well. Be safe while you're wrenching!

 

Here’s one that just came to mind.

I’ve got a transmission air to liquid cooler/thermostat, etc.

Is there any detrimental things I ought to be aware of if driving city/interstate in temps ranging from 105-118 degrees with the thermostat pinned open?

I conducted an experiment yesterday driving upgrade on the the interstate (98-102* ambient) speed 65-75 for 16 miles with it pinned open and then pin removed (closed). Not towing or loaded up.
This particular part of the interstate has a significant hill of 5-6 miles.

Pinned open it maxed at 194*.
Pin removed it maxed at 204*

Any thoughts on this?

 

I don't think its going to make much of a difference, the issue with leaving it pinned is warm up temp, especially in the colder months since the torque converter wont even lock up until its over 100°. Optimal temp is around 185° thats when the thermostat opens up. I pinned mine once just to experiment but I dont really see any benefit since the thermostat will open once it's up to temp. By pinning its just going to take longer to get up to temp. I dont think you will have any negative affects by leaving it pinned when its hot out but it wont really have any positive affects either, 10° difference is negligible.

 

Bought my tundra new, had the trans, both diffs and transfer case fluid changed at 44,000 miles. I drive daily like the bandit. The service advisor guy that drove in, in a junk Korean car was like you’re good til 100k you’re wasting your money. I hate having to fight with people and explain preventative maintenance, longevity. I plan on having this truck for a million miles I told him and that the tundra bros online teaching me the right way.

 

Dealers have no incentive to preserve the longevity of your vehicle.

 

Thanks for the information, especially the temp the thermostat opens up. I’d wondered about that but couldn’t find the answer. So, thanks!

I was on the freeway again today running errands. Ambient 102-105*. Had it pinned open and got it to 180* at 80. It hovered around 176 going the speed limit. The cooler I installed works wonderfully in hot weather with the t-stat pinned open.

 

Which cooler did you use? I have the Setrab 20, unpinned on the highway I stay right around 185° unless I'm going up inclines but then it drops right back down.

 

I have the ‘MHX-514 Improved Racing’ cooler from Genuine Cooling Systems.
I went the website just now and although there’s a link to its installation it appears it’s no longer offered for sale.

It does the job very well. I think it’s designed primarily for use in extreme heat. I recently drove thru Las Vegas, NV. It was 116-118* on the freeway. The big “test” was after crossing over Hoover Dam on the new bridge there’s a significant hill to climb. My truck was loaded with gear but not towing. I had the thermostat pinned open and was doing 60-70mph. The transmission temp never exceeded 185.

When I got off the freeway and took a
bathroom/food break it hit 197 doing a small amount of city driving. Probably would have gone higher had I driven more in the city. I got back on the freeway and it dropped back to down even as far as 176 on flat grades but I’d say the average temps were 181-185.

I forgot to add that I did away with the WS fluid shortly after installing the cooler and have been using AMSOIL ever since.

 

Gutcha! Yeah he switched to Setrab after that cooler, I forget the reason, might have just been due to stock, just like how I have the setrab 20 but he only offered the 20 because the 15 was out of stock for so long, now I believe he just offers the setrab 15.

 

I did the transmission service a couple of days ago, and I'm positive it was worth it!

The reason I'm so sure is my truck started making what I call a "bus whining" noise a while ago. It's really hard to describe, but I have noticed that back in the days when I rode buses. It happens right after you let off the accelerator, for a second or so. That noise almost never happens now.

Didn't drop the pan. The fluid didn't look nearly as disgusting as the gear oil from the differencials.

Found some interesting things:

1. The transmission must have been overfilled from the factory. The first drain was 3l, even though the manual says the pan capacity is 2l. The next two drains were under 2l. Unfortunately I didn't remove the overflow bolt before the first drain, so I can't confirm it 100%. In total I drained 6.6l and filled 6l. That was all I had, but I'm reasonably confident I overfilled it slightly, but definitely less than it was from the factory.
2. The Sequoia doesn't seem to have the OBD port trick to short the two pins to go into transmission service mode. One of those pins has no conductor in it. And Techstream refused to do the pin connection, with an unreadable reason. So I had to use an infrared thermometer.
3. The brakes don't seem to work when all the wheels are off the ground and spinning even a little bit fast. Had to shift to neutral to get them to stop spinning. That felt really scary, but seems like it must be by design.

I'll get another bottle of ATF, and double-check next week that it's filled properly, but I'm reasonably confident that it is.

Thanks for all the advice.

 

Most OBD readers can see the pan temp, I personally use OBDLink MX+. I definitely suggest doing the check bolt with an OBD to ensure the correct level. Also I have no idea how much it matters but there is an option in Techstream to reset the ATF Thermal Degradation. Its a number that goes from 0-62000~. Toyota recommends replacing the fluid if the number is over 50000 and also recommends reset it when 50% of the fluid is replaced. I just reset mine for the first time at 47,000 miles but have replace the fluid before without reseting it. It was only at 2705 before the reset.

 

Just returned from a 5k mile trip from the southwest to the northwest and back.

I kept the thermostat pinned open all the way up and unpinned all the way back. The route was identical both ways with one exception. I made a side trip into Death Valley on the return leg.

For the trip the ambient temp ran between 76* and 118*. Truck loaded with gear and water not towing. Trans temp averaged 185 on the way up and 197 on the return. It hit 203* doing 70mph coming up out of Hoover Dam but returned to 197 as soon as I leveled out.

Conclusion: Best dang truck I ever owned.

p.s. saw more than a dozen manufacturers test vehicles in Death Valley. The ones all covered in funky camo material or black vinyl. Most looked to be little sedans or little SUV’s.
I’ve only seen those in photos so seeing them on the road was cool.
Sorry bro’s, I didn’t get any photos.

 

Ditto on all the above…..
Unfortunately there isn’t a consensus with Toyota on much of anything.

What Yakeng said above in post #39 about “dealer incentive” is spot on.

I heard from an out of state Toyota parts guy that this forum is a very good place to get info, ideas and specs. Just gotta sift thru the non-essentials and keep asking questions, etc. The straight-shooters will make them selves obvious.

 

@hagrid - get in here.

 

If you do not have the transmission cooler then absolutely without a doubt change it. Previous owner of my 2020 took excellent care of the truck changed the oil every 5k miles religiously. I bought the truck and it’s in like brand new condition. However he towed a LOT with it and after I bought it the transmission failed two weeks later with only 45,000 miles on it. Fluid was burnt and the transmission was replaced under the power train warranty. I can’t stress enough how important it is to change the fluid if you do in fact tow a lot and it’s a model that they removed the cooler on.

 

That's the 2021 Sequoia Limited. Unfortunately. I was under the impression that this model comes with the towing package, but it doesn't.

Given how easy the fluid is to replace (once you figure out the details) I'm going to start doing it a lot more often. I worry that I may have caused some damage, with the crazy mountains I climbed up and down, but other than a hint of whining noise - it doesn't have any problems.

I blame the lack of a good maintenance schedule. The one I compiled was a sort of average of all the different ones I could find. Can't turn back time now.

 

Dang I’m currently having this same debate… I’m not sure if I should have my transmission fluid changed. I have a 2018 tundra with 76k miles. Luckily I have a transmission cooler on mine. I called my local dealer and they said they do a flush for $300 which did not seem to bad honestly. I only tow like 4k pounds a few times a year but mostly it’s just used as my daily. Sounds like the consensus on this thread is to do the flush.

 

I wonder how they do the flush as I was under mine right after they did it and the fill plug and drain plug had not been touched.

 

You can add a cooler to the sequoia, same one as the tundra fits.
https://genuinecoolingsystems.com/product/setrab-15-row-5-7l-tundra-2019-2021/

 

If you trust them it might just be easier for you to have them do it. It’s definitely not a hard procedure it’s just different and is way easier with 2 people. But I would definitely do it either way. It can’t hurt to refresh that fluid and $300 isn’t bad. Key thing is if you trust them to do it right.

 

So I just called an asked details on their process at my local dealer and this is what they told me. Its a full flush for 299. they will push a cleaning solution through to get all the gunk out and flush it clean. Then suck everything out with a vacuum suction then use a machine to push in the new fluid. I think I will probably go ahead and do it.

 

Consensus I’ve seen is this is one of the worst things you can do to your transmission. Nothing should go in the trans except ATF. They will never get 100% of the “cleaning solution” out so you will have contaminated oil moving forward.

 

Interesting take on this… so does every dealership do it differently then? I’m also not apposed to doing a drain and fill on my own either.

 

Yes, the service departments are independently owned - Toyota doesn’t not control how they operate or the methods used. Everyone I’ve seen that has looked at the Toyota service manual re transmission has indicated Toyota’s recommendation is a drain and fill procedure - not a pressurized flush.

 

That’s what’s so frustrating about these transmissions. There is not a clear way as to have them serviced. If dealerships are all doing it different that just seems weird.

 

Don’t over think it. Just watch the car care nut on YouTube. He explains it perfectly. It’s more of a refresh every 60,000 miles. I’m with others on the flush tho. Don’t have them push anything through it. They will knock contamination loose and cause worse issues. Also that’s not the Toyota procedure.